Reevaluation of the Braginskii viscous force for toroidal plasma
نویسنده
چکیده
The model by Braginskii for the viscous stress tensor is used to determine the shear and gyroviscous forces acting within a toroidally confined plasma. Comparison is made to a previous evaluation which contains an inconsistent treatment of the radial derivative and neglects the effect of the pitch angle. Parallel viscosity contributes a radial shear viscous force which may develop for sufficient vertical asymmetry to the ion velocity profile. An evaluation is performed of this radial viscous force for a tokamak near equilibrium which indicates qualitative agreement between theory and measurement for impure plasma discharges with strong toroidal flow. PACS numbers: 28.52.-s, 52.30.Ex, 52.55.Fa
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